login
Permutations of decimal digits 1-9 giving three 3-digit primes.
2

%I #5 Jun 18 2013 21:17:46

%S 127463859,127643859,127859463,127859643,149257683,149257863,

%T 149263587,149263857,149563827,149587263,149653827,149683257,

%U 149827563,149827653,149857263,149863257,157463829,157643829,157829463,157829643,163457829

%N Permutations of decimal digits 1-9 giving three 3-digit primes.

%C There are 816 such permutations, last six a(811)-a(816) being 983467521, 983521467, 983521647, 983641257, 983647251, 983647521.

%H Eric M. Schmidt, <a href="/A115301/b115301.txt">Table of n, a(n) for n = 1..816</a> (complete sequence)

%e 127463859 => 127, 463, 859 all prime; 127643859 => 127, 643, 859 all prime etc.

%t Select[Permutations[Range[9]],Union[PrimeQ/@FromDigits/@Partition[ #,3]]--{True}&]

%K fini,full,nonn,base

%O 1,1

%A _Zak Seidov_, Mar 04 2006